1. Field of the Invention
The present invention relates to a projection display device and a light source control method thereof.
2. Description of the Related Art
A head-up display (HUD) device for a car in which a windshield of a car or a combiner arranged near the front of the windshield is used as a screen, and projection light is projected onto the screen so that an image is displayed is known (see, for example, JP2012-003092A). According to this HUD, a user can view an image that is displayed on a windshield or the like by the projection light projected from the HUD, which is superimposed on a scenery ahead of the own vehicle that is on the back side of the windshield or the like.
There is an HUD that adopts a so-called field sequential scheme (surface sequential scheme) of sequentially rapidly switching light incident on a light modulation element, such as a digital micromirror device (DMD) or a liquid crystal display element, to red light, green light, and blue light in time series, and combines afterimages corresponding to the respective color lights on a retina of a person to obtain a color image.
JP2012-003092A describes a device that projects an image using a field sequential scheme. In this device, it is possible to project a high-quality image according to ambient brightness by providing two types of light sources that emit respective color lights including a light source having a large light emission amount and a light source having a small light emission amount.